| 摘要 |
PURPOSE:To perform the satisfactory drift compensation and the control of the identification threshold value in a simple constitution by amplifying the output of 8 photoelectric transducer to an input signal and then comparing the amplified output with the reference value. CONSTITUTION:An optical input signal is converted into an electric signal by a photodiode 1 and branched into two pieces by an amplifier 2. One of both electric signals is inputted to the negative input side of a comparator 6 with the other signal inputted to an LPF 3 respectively. The pulse signal undergone the band limitation through the LPF 3 is inputted to a peak detector 4. Thus the peak value of the base level of the pulse signal is detected and added with the offset voltage through an adder 5. Thus the reference value of comparison is obtained and then inputted to the positive input terminal of the comparator 6. Then the reference value is compared with the output of the amplifier 2. Thus the data can be identified. |
